AWS CodeCommit, a fully-managed source control service, is now available in the AWS GovCloud (US-East) Region. CodeCommit makes it easy for companies to host secure and highly scalable private Git repositories.  

from Recent Announcements https://aws.amazon.com/about-aws/whats-new/2019/05/aws-codecommit-now-available-in-the-aws-govcloud–us-east–regio/